For three seasons, trainer Chris Powell has helped people transform their lives. It's all documented for the show "Extreme Makeover: Weight Loss Edition."

Kerry Shanahan is a casting director for the ABC show.

"The feeling I get when watching the show is unlike any other. What you see on the screen with Chris is, he's humble, he's caring," Shanahan said.

Shanahan is at the Franklin Planet Fitness, searching for 12 participants who can dedicate a year for the fourth season.

"It's 365 days, and you're at home addressing issues that got you to this weight," Shanahan said.

Casting directors like Shanahan are visiting 13 cities in all to meet people who need to lose 50 percent or more of their body weight.

"Somebody that makes a good contestant is somebody who has the drive and has the will right now to want to change," Shanahan said.

This is a second visit to Wisconsin for the show.

They are looking for people 18 and older who will spend the next year exercising, changing their diet and even soul searching to drop the pounds.

"We always get a good crowd from the Midwest. Wisconsin delivered last season, and we're hoping it can deliver again," Shanahan said.

Anyone who is interested and meets the basic requirements, should go to the Planet Fitness in Franklin from 10 a.m. to 5 p.m. Saturday. The casting director recommends coming early, but not before 7 a.m.

The Franklin Planet Fitness is located on 27th Street by College Avenue. Bring a non-returnable photo with you.

The casting directors won't say how many participants were from Wisconsin for Season 3, but one is a Waukesha County detective.

Read more about his transformation from WISN 12 News' partners at the Waukesha Patch.